Late on Thursday evening, the US military said it had launched 59 Tomahawk land attack missiles targeting the Al-Shayrat air base in Homs, which American intelligence had indicated that Syrian planes carrying deadly chemical weapons took off from.

Reacting to the news on Friday morning, a spokesperson for Number 10 said: "We believe [it] was an appropriate response to the barbaric chemical weapons attack launched by the Syrian regime, and is intended to deter further attacks."

Jim Watson / AFP / Getty Images

US president Donald Trump delivers a statement on Syria from his Mar-a-Lago estate in Florida on 6 April 2017.

"Overnight, the US has taken military action against the Syrian regime, targeting the airfield in Shayrut which was used to launch the chemical weapons attack earlier this week," the Number 10 spokesperson told BBC news.

Defence secretary Michael Fallon, speaking to BBC Radio 4's Today programme, reiterated the government's support of the strike action. He said the UK, which was not asked to take part in the strikes, had been given advance notice of it by US defence secretary General James Mathis.

Fallon said the UK would not be taking part in military action, referencing a 2013 parliamentary vote in which the House of Commons narrowly rejected David Cameron's proposal to intervene in the country. He said any British military involvement in Syria would require approval from parliament.

"We fully support the US and the call last night to lead Syria towards a new political settlement," Fallon said. He added that the government did not believe this was a move towards a large military action, but should instead be seen as a warning strike.

But Labour leader Jeremy Corbyn criticised the British government’s response to US strikes. He said the government should “urge restraint” to the Trump administration, and "throw its weight behind peace negotiations and a comprehensive political settlement".

“The US missile attack on a Syrian government air base risks escalating the war in Syria still further,” Corbyn said in a statement.

While the “horrific” alleged chemical attack requires an urgent investigation, he said, “unilateral military action without legal authorisation or independent verification risk intensifying a multi-sided conflict”.

Instead, the Labour leader called on world leaders to “urgently reconvene the Geneva peace talks” and put “unrelenting international pressure for a negotiated settlement of the conflict".

He said: “The terrible suffering of the Syrian people must be brought to an end as soon as possible and every intervention must be judged on what contribution it makes to that outcome.”

MP Alex Salmond, the SNP's foreign affairs spokesperson, criticised the government's calls supporting the strikes. He attacked the Trump administration's intervention, which he said introduced a "further and dangerous unpredictability" to an already complicated civil war.

“If the position of the UK Government is merely to back any US action whatever it may be then they will find themselves struggling to keep up with the twists and turns of the Trump administration," he said in a statement.

Salmond said Trump has a political interest in "humiliating his predecessor and in distancing himself from Russia. The UK has no interest in either, with only this week the Foreign Secretary attempting to reset UK/Russian relations."

“All of this is no substitute for a real policy to end the tragedy of the Syrian civil war," he said, and called on the UK to reinstate the Dubs amendment on unaccompanied child refugees.

Echoing Corbyn's calls for further verification, he said: "Such strikes should take place only after detailed examination and assessment of the storage facility and the delivery mechanism."

Tim Farron, the leader of the Liberal Democrats, backed the strikes, saying: "The attack by American forces was a proportionate response to the barbarous attack."

Crispin Blunt, chair of the Commons foreign affairs committee, told the BBC the strikes were a "carefully calibrated and appropriate response", so long as the information was correct.

"The reason I would have doubt and express doubt [over the information] is this doesn't make any sense from the Syrian government, they would know this use of chemical weapons would get this response," he said. "The overall conflict is moving in their direction."

Blunt, who voted against action in Syria in 2013, said the strikes could be useful in bringing political pressure against the Assad government – especially during the talks in Brussels and at the UN taking place this week.

Deputy Labour leader Tom Watson, speaking to the Birmingham Mail, said the US strikes were "proportionate".

Watson, MP for West Bromwich East, said the attack did "appear to be a direct and proportionate response" following claims that the Syrian government used chemical weapons against its own people. "Indiscriminate chemical weapons attacks on civilians can never be tolerated and must have consequences," he said.

On Friday morning, the Syrian army released a statement and said six soldiers had died. It stated that it would continue to "crush terrorism" and restore "peace and security to all Syria". Later, Syria state media reported that nine civilians, including four children, had died in the strikes, according to AFP.

Meanwhile, Russian spokesperson Dmitry Peskov called the strikes an "aggression against a sovereign nation" and called for an emergency meeting of the UN. Russia has provided significant military support to the Assad regime.

Vladimir Putin's spokesperson went on to state the strikes were an "attempt to distract the world from civilian casualties from US military action in Iraq" and "do significant damage" to "US–Russia ties". No Russians were believed to have died in the assault, Interfax news agency reported.

The Russian foreign ministry put out a statement saying it was "obvious that the US cruise missile strike had been pre-prepared. It is clear to any specialist that Washington made the decision to strike before the events in Idlib, which were only used as a pretext for a show of force."

Crucially, the ministry said it would suspend an agreement with the US that prevents midair collisions over Syria. The September 2015 memorandum meant the two nations exchanged flight information and paths to prevent incidents and ensure flight safety, AP reported.

NATO was warned ahead of the strikes. A spokesperson for chief Jens Stoltenberg said it would not be making a statement, and referred the AP to the US government.